The only ethical psychological "tactics" in my opinion are 1) getting opponent out of "book" by playing "unusual" moves, 2) playing "trappy" openings if you want to risk opponent already knowing the trap (e.g. Blackburne Shilling, 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nd4 (4.Nxe5? Qg5)), and 3) if opponent is not using good time management, that is, playing either too slowly or too quickly, then shade your own time management in the opposite direction -- play just a little quicker against dragging opponents and a little more deliberately against impatient opponents.
getting opponent out of "book" by playing "unusual" moves,
playing "trappy" openings if you want to risk opponent already knowing the trap (e.g. Blackburne Shilling, 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nd4 (4.Nxe5? Qg5)), and
if opponent is not using good time management, that is, playing either too slowly or too quickly, then shade your own time management in the opposite direction -- play just a little quicker against dragging opponents and a little more deliberately against impatient opponents.